Tetracyclic compounds and process of making same



Patented July 20, 1943 'rnrnaor'crlrc COMPOUNDS AND rltocriss OF 'MAKING SAME Leopold Ruzlcka and Moses Wolf Goldberg, Zurich-Switzerland, assignors to Ciba Phat-ma .qceutical Products, Incorporated, Summit, N. J.

@No Drawing. Application January 22,1941, ;Se-"

rial No. 375,54}. In Switzerland January 17,

It has been observed that" valuable tetracyclic compounds are obtained by .ring exten'sicnfrom any desired substituted derivativesof the steroid, ring-homoand ring-nor-steroid series containing at least one hydroarom'atic ring'which possesses a side chain containing a reactive, monovalent substituent attached to j the carbon atom adjacent to the ring by splittingiloff the said monovalent substituent. {With regard to the nomenclature of: Helveticafchimica Acta23, .366 (1940) .1

It appears that, by displacement of a ring carbon atom to the carbon atom of the side chain adjacent to the ring, a, radical-like compound is formed intermediarily which, if necessary with The parent materials may contain one or more side chains possessing reactive monovalent substituents in any desired position's'o'f their hydro arornatic ringsjor example, in the ,2, 3, 6, '7, 12,16, or 17 positions." As reactive, monpvaljent substituents, mention maybe made crime or 'substituted hydroxyl, thiol or amino groups. The

ring carbon atom to which is attached theside chain may carry, in addition to the side'chainhydrogen or, for example; free or substituted hydroxyl, thiol or amino groups as substituents. Furthermore, the parent substances'may also 'contain other substituents, for instance/free or substituted hydroxylgroups, keto groups v-,(e lth ei)fre'e or present in the form of their enol derivatives), halogen atoms, free or substitutedamino group's, free or esterified carboxylfgroupsjand sooni The parent substances are derivatives of the steroid series; 'i. e., cyclopentanopolyhydro phenanthrene compounds, or compounds which may be derived from these by ringextension (ring-homo-comp ounds) or ring contraction (ring-nor-compounds) of one or more of the'iour rings. The amines suitable for use as parent sub stances may be preparedirom saturated or unsaturated nitriles of, the steroid,,,ringho m0,-. and

after splitting off watery-Furthermore suitable ating. (01. 260-586) amines maybe obtained' by reduction of the oximes of corresponding carbonyl compounds or by degradation of acetic acid derivatives of the series mentioned; Suitable amino or halogen de rivatives may alsobe obtained, for example, by splitting up semicyclic'oxydo compounds of the series mentioned with ammonia, amines or hydro gen halides. The latter par'ent" materials may also be obtained from hydroxymethyl derivatives by replacement ofthe hydroxyl group byihalogen. In splitting off the reactive, mon ovalent substituents, all the-methods known'and described in the literature for this purposemay be used. (See,- for example, Karrer, Lehrbuch vder organischen Chemie, 6th ed,, pages 661 etsqq sqq.) V For e xarnpla'forthe splitting'ofi of a halogen atom or of athiol group'use may be made or metals, their oxides or salts, for instance, silver, lead, copper, zinc, mercury oxide, silver salts such as silver nitrate, and'so on. The splitting on of a hydroxyl group may take' place by'heating and/or by the use o f'substances acting as catalysts, acid agents, such as inorganic or organic acids, also by acid anhydrides or acid halides. sp i sjpfitb n, am no group m y ake place 'by'the direct splitting ofi'oi ammonia orby indirect ways, through intermediate stages which may or maynot be isolated. For example, the salts of the primaryamines; or of the secondary or'tertiaryamines which may easily lbeprepared therefrom by known methods, are'subjected to a thermic decomposition, if desired,',"uhder1 d iminished pressure. In the first c'as'e, the eliminationof the amino grouptakesplace with splittin splitting v01f of a a primarykorj secondary amine.

known; O

It is also possible to convertfthje amines mentioned into the. 7 corresponding quaternary ammonium basesand then to splitthese in known manner. Furthermore, the primar-yamines may be diazotiz ed by. means or nitrousacid or -itsderivatives; the diazo compounds which appearas intermediate products arenot stable and readily split ofl" nitrogen. :The splitl ng off of organic acids, f al ohols or of phenols also takes place by means of agents or proceduresof themselves The splitting on of the reactive group takes place preponderantly by rearrangement of the tetracyclic ring structure present, that is to say, by ring extension, the carbon atom of the side chain adjacent to the ring being built into the ring system. If, for example, cyclopentanopolyhydrophenanthrene compounds are used as parent materials, and if the side chain containing the reactive group be in the ring D, the reaction product formed then possesses a ring D which has been extended to a six-ring. In this manner, derivat-ives of the polyhydro-chrysene series are obtained. If the side chain had beenunited to the ring A, B or C of the cyclopentanopolyhydrophenanthrene nucleus, the reaction products obtained contain rings wit seven carbon atoms.

Analogous ring extension occurs when ring homoor ring-nor-steroids are used as parent the 3-epi 17 dihydroxy-17-aminomethylandrostane from androsterone cyanhydrin. If 3-ketol'l-amino methyl-androstane be used as parent material, deamination with nitrous acid also yields an oxyketone, CzoHazO-z, of the perhydrochrysene series; but this substance has the keto group situated in the ring A and the hydroxyl group in the extended ring D. In an analogous manner, for example, a, six-ring alcohol of the polyhydro-chrysene series or its esters or others may be obtained by extension of the five-ring of unsaturated 1'7 aminomethyl androstane or -oestrane derivatives. From the corresponding 17-hydroxymethyl compounds, ring extension products having a double bond in the new extended ring are obtainable by treatment with an materials. Side chains, each of which has a, re-

active group attached to the carbon atom adja cent to the ring, may also be present simultaneously in several rings of thetetracyclic nucleus; in this case several rings will be extended simultaneously.

The reaction products obtained according to the present invention contain in the extended rings a newly introduced keto group, a free or substituted hydroxyl group or even adouble bond, depending upon the type of the agent used and the further substituents at the ring carbon atom which carries the side'chain. For example, ringc-xtended ketones can be obtained if the substituent named be a free or substituted hydroxyl, thiol or amino group, and ring-extended free or substituted secondary alcohols or their dehydration products if the substituent be a hydrogen atom. According to the nature of the rearrangeirient taking place, various structurally or stereo isomeric products may naturally be formed. Compounds formed which have double bonds may subsequently be converted into ketones in a manner of itself known, by the introduction of oxygen, for example, by way of the corresponding oxides and/or glycols.. Ketones resulting or prepared in this way may be converted into secondary alcohols according to the reduction methods usual for this purpose. .The latter finally may be converted into their esters, for example, their acetates, propionates, butyrates, benzoates,.substituted carbonates, phthalates, or succinates in known manner by esterifying agents or into their others, such as their methyl, ethyhbenzyl, triarylmethyl ethers, by. means ofetherifying agents. II ketone groups are present-eventually in addition to hydroxyl groupsin the molecule of the new compounds, enol, derivatives, viz., enol esters and enol ethers, may be obtained by the action of the esterifying or etherifyingv agents.

A new oxyketone, CzoHazOz, carrying the keto group in the seven-ring and thehydroxyl group in the five-ring, is obtained by the extension of he ring A of 3,l7-dihydroxy3-aminomethylandrostane to a seven-ring according to the new process, for example, by diazotization. The amine used as starting material is itself obtainable by the'hydrogenatlon of 3-lreto-androstanel'l-ole-cyanhydrin. Starting with 3,l7-dihydroxy 17 aminomethyl androstane, which is formed by reduction of the-cyanhydrin of 3- hydroxy-androstane-l'l-one or by catalytic hycirogenation of the cyanhydrinof"A -3-hydroxyandrostene l'l-onean oxyketone,'- C20H32O2, of the perhydro-chryseneseries is obtained analogously, in which the keto group'is situated in the ring D which is extended to a six-ring. An'eprlmeric oxyketone may be prepared by way '01 proved to be very active by biological tests.

. Example 1 100 mg. of 3,17-dihydroxy-l7-aminomethylandrostane acetate are dissolved in 2 ccm. water with theaddition of some drops of glacial acetic acid, and-an. aqueous solution of mg. sodium nitrite is added to the solution. v Nitrogen is evolved. The reaction mixture is allowed to stand overnight at room temperature, when the reaction product is removed by filtering. .After washing it with water, it is recrystallized several times from aqueous methyl alcohoL- Lustrous flakes areobtai'ned which melt at 193195 C'. The substance is an oxyketone of the prehydrochrysene series, Cad-1:202. which probably corresponds to the formula f CH3 CH1 0 The acetate, prepared by acetylation with acetic Y anhydride inpyridine melts, after recrystallization from etherpentane, at 124-126 C. The semicarbazone, prepared in the usual manner, melts at 252-254 C. after recrystallization from methanol. In a similar manner there are also obtained others of this hydroxy. ketone such as for instance the triarylmethylether, benzylether or alkylether.

From ketones of the polyhydro-chrysene series, preparedjthus or inother ways, for example, totally synthetically, after the addition of correspondingly substituted side chains, tetracyclic compounds with 3 six-rings and one seven-ring may be obtained by further ring extension.

In order to'obtain the starting material used in this example there may be proceeded as follows:

'800 mg. of A -3,17-dihydroxy-androstene-17-mtrile (M. P. 206 C.) are dissolved in ccm. of hot glacial acetic acid and are hydrogenated with the aid of 400 mg. of platinic oxide catalyst, After 3 molecules of hydrogen have been absorbed the hydrogenation is interrupted, the solution is filtered from the catalyst, concentrated to a small volume in vacuo, diluted with water and then filtered'from'small quantities of insoluble substances. The clear, aqueous solution is evaporated in vacuo and the residue is dissolved in methanol. When ether is added, 3,17-dihydroxymethanol and the calculated quantity of methanolic potassium hydroxide solutionds added. Qn dilution with pwater, 3,l7.-dihyd roxy -,17- aminomethyl-androstane crystallizes It may be recrystallized o metha ol. anima m ltsn By acetylation with acetic anhydride in absolute pyridine, the triacetyl derivative of 3,17- dihydroxy- 17 -aminomethyl-androstane is formed. After recrystallization, from ether-pentane it melts at 166 C. Instead of the acyl groups there may be introduced in analogous manner also other radicals capable of being split off again by the aid of hydrolyzing agents and thus for instance other esters, s'uch'as propionates, butyrates, benzoates, or then ethers, such as triarylmethyl ethers, benzyl ethers or alkyl ethers may be obtained. I

.Example 2 :5

500 mg. of 3 acetoxy lf7-hydroxyel7 amino methyl-,androstane acetate areldi'ssolved in"0,5 'ccm'. glacialacetic acid and.lq'ccm'otwater. aqueous solution of 250 mg. of sodium nitriteiis run in and the f re'ac'tio'n mixture isfallowed to stand overnight at room temperature. [The reaction product which is formed with'the 'evolu tion of nitrogen is filtered oil, washed with water and dried. It'is'dissolve'd inben'zene-petroleum ether (:80) and the solution is filtered 'through a column of 16 mgiof activated aluminium oxide. The column is eluded withthe same mixtur of solvents and the united extracts arejevaporated to dryness. The residue is recrystallized from ether-pentane, 250 mg. of the acetoxy-ketone described in Example 1, melting at 124-126 0., being obtained. 1

' In order to obtain the-starting materialthere may for instance be. proceeded as .follows:

700 mg.-of A -3-acetoxyel l-hydroxy-androstene- 17-nitrile is dissolved in 40 vccm. oiglacial acetic acid. 350 m. of platinic oxide catalyst is added, and the reaction mixture is shaken with hydrogen at room temperature. The quantity of hydrogen equivalent to 3 molecules is absorbed within minutes. catalyst, concentrated in vacuo, diluted with water, and filtered free of small quantities of insoluble impurities. The clear, aqueous solution is evaporated to dryness and the 3-acetoxy-17- hydroxy-l7-aminomethyl-androstane acetate obtained is recrystallised from methanol-ether. It

melts with decomposition at about 235 C. Yield is6'70mg. 4,

If instead of from a 3-acetate thereisstarted from, a ,c'ompoundwhicli in 3-position is substituted by another radical'capable of being con.-

.verted into a hydroxyl gr'oup by fthe aid of hydrolyzing agents,' there"'are' obtained in an analogous way thev correspondingly substituted amines. By energetic' 'action of esterifying or etherifying agents, respectively, these compounds may be transformed intojany diesters or esterethers, respectively. a i 1 I I fiE mampZe 3 d 40o mg. of 'a e i,imdih d cx iv aminom'ethylandrostane acetate are dissolved'in 8 com. water with the addition of -a few drops of glacial acetic acid, and anaqueoussolutidn of 200 mg.

sodium vnitritepis"added. 5 After. allowingv the mixture to stand I overnight at roomitemperature,

the reaction product-which has been formed with evolution of .nitrogen is filtered .ofi. After drying, it is dissolved-in a'mixture of .benzenepetroleum ether 00:80) andthe solution filtered througha column .0112 grams of activated aluminium oxides .The .columnis washed with the samexmixture of; solvents and is then eluted with benzene-ether (7012.30): The benzene-ether solution is evaporated, and the residue is recrystallized from -ethyl.;.acetate and aqueous 7 methyl alcohol, leaflets being obtained which may for instance be proceeded as follows:

500 mg. of 3 epi,17-dihydroxy andr0stane-17- The solution is filtered from the decomposition.

melt at 203-305"v 'C. The'product isan oxyketone, C20H3202, of the probable formula CH: v

absolute pyridine, after recrystallization from ether-pentane, melts at 151l 52 C. A benzoate may also bewobtainedv in an analogous manner. The semicarbazone obtained from the oxyketone in the ;usual manner mayv be recrystallized from methanol and then :melts at about 310 C. with The oxyketoneor its may-be converted into the corresponding diole or its monoacetateor-benzoate, for example, by the action, of sodium in propyl alcohol or. of hydrogeninthe presence of,a' catalyst. 1 These reduction products maybe. further ,esterified, and thus, for, e amples 'diacetate or anacetatebenzoatem'ay be obtained} f In order to obtain the starting material there name are dissolved in sojc m. ofglacia l acetic acid a'nd'are hydrogenated at room temperatureafter addition of. 250 mg. of platinic'oxide catalyst, 2 mole cules oi hydrogen being absorbed. The catalyst is removed by -filtratiorn.and the filtrateisworke'd up as described in Examples 1 and"2. The 3'-epi',17-.dihydroxy l7-arninomethylandrostane acetate'obtained, after recrystallization from me'thanol 'ether, melts withldecomp'osition at about 200 C. Yield=420 mg. V

The free amine, gobtained from the acetate by saponification with the calculated quantity of potassium hydroxide in methanol, may be recrystallized from methyl alcohol and then melts at 206 c.

Example 4 and fs'ubsequent oxidation of the latterfaccording to Opper1 at 1'e1"s method. 500 mg. of'the said ar'ninejare'd'issolVed in 05 com. glacial acetic acid and ,10 cc.]water.f An aqueous solution of 250 mg. sodium nitrite is run in and the reaction mixture is allowed to stand overnight at room temperature. j Th'e reaction product, which.

precipitates, is taken up in ether and the'ether soluti oniafteri washing v and drying, is evaporated todryn ess v The residue istaken up'inibenzeng;

acetate or benzoate,v

of. 20.: grams activated: aluminium, onidie. who columniis: washed with. the same. solvent mixture, then with benzene and finally with benzeneether (80:20 The-extract-obtadned zene-ether is: recrystallized several times hum ethyl acetate-hexa.me and then melts 11814189 C; It is an oxyketouc ofthe perhydro-ahsysuue series, having the probablefiormuh out Lenon;

The benzoate, preparedirr the usual manner with benzoyl chloride in pyridine, melts at Example 5 200 mg. A 17-aminomethyl-androstene-3-one, I

prepared from A -3-hydr0xy-pregnenic 21 acid by degradation by Curtis" method,jwith intermediate protection of the hydroxyl' group and S sequent oxidation or the sam according to OD- penauefis method; are dissolved in 4 com. of water by the addition of a few drops of glacial acetic acid, and an aqueous solution 01' I00 mg. of sodium nitrite is added. Nitrogen is evolved. The reaction mixture is aliowedto stand over.- night at room temperature, when the precipitated reaction product is filtered ofl. After washing it with water, it is tractionally crystallized from a mixture ofhexane-acetone. In this manneigan oxyketone is obtained, Gaol-13002, a member of the polyhydro-chrysene series, having the probable formula CH: OH

It proves to be. a highly active compound otth'e male hormone type. By gentle action 01! esterifying or etherifying agents it yields monoestersor monoethers, respectively, jfor. example, an acetate, a propionate, n-butyrate, benzoate, chlorocarbonate,, succinate, triaryimethylethen; benzytether, 'alkylether, etc. By energeticaction, dlesters, diethers. or ester-ethers, are obtained by enolization, for example,,the"diacetate or the dipropionate. The 3-keto group maybe converted instead of into enolest'ers or enolethers aiso into acetals or mercaptals, suchas for instance-moo a giyrolacetai'; propan- LZ-dioI-acetaI.

iii)

Empted 7 30 o1 A -1 1 aminomethyl-androstene-iionei pmd by-thedegradation oi A -3-hydroxy- MMQcJi-a'citl' morainete Curtis" method 'mkixwemuluh protection of the hydroxyl group; 'areemsed te react with' nitrous acid as Med in -Bampl 5. In -this 'manner, a dick, {of the lielmd'ro-chrysene series is tamed-having the probable formula '500 mg. of A -l7-hydroxyrnethyltandrostener3- one are. distfliedrm vacuo with anhydrous: oxalic acid. 'A'lmtonc is obtained from. the reaction pendant by ravlm' s ga column. of alumiimx mridei This lcetone' probably conforms (08h. hm v This product may also be obtained by treating the parent. material iorv /2 hour with formic acid orby the action. of phosphorous oxychloride in a tertiary amine. It is also available by the treatment. 0! A -l'1-hal'ogenmethyl androstene-3-one withan agent which eliminateshydrogen halide. The doubly unsaturated ketone is taken up in other; An excem of lflpercent. ofosmium tetroxide in ether is added; and the mixture is allowed to stand for 4 days, when the ethereal solution is evaporated to dryness and the residue is heated for two hours at the Boil with ten times its weight (11' sodium. minute in 1.091 times its weight of mi! andifi times'ita weightof alcohol. The reaction mixture iii-then fiitened' attire.- pump, and tin filtrate: is extracted with chloroform. The

-rm mliitionyields u dimwketone formed by s mulation ol. the double: bond in. ring D. This may be converted into an diketone of the probableformula v .CHV, g

by distillation in vacuo over potassium disulphate.

The diketone may also be obtained from A -17- hydroxymethyl-17-hydroxy-androstene 3-one by the help of dehydrating-agents. This A -17-hydroxymethyl-l7-hydroxy-androstene-3-one v may unsaturated itself be obtained by the reduction of a A -3,17-f

dihydroxy-etiocliolenic acide'ste'r with 'sodiurnin alcohol and subsequent partial oxidation in the 3-position by Oppenauers method.

If the diketone be heated with ethyl orthoiormate in benzene solution, its 3-mono-enol ethyl ether is obtained. In a similar way, other 3-enol-ethers or .even 3-acetales or -mercaptales may be obtained, for example, those derived from divalent alcohols or thioalcohols.

What we claim is: i

1. A process for the manufacture of tetracyclic compounds by ring extension, which comprises reacting a compound of the steroid series which containsat least one hydroaromatic ring havingin. '17-p0siti0n aside chain containing'a'reactive monovalent substituent, selected from thegr'oup consisting. of amino, hydroxyl, substituted amino capable of being hydrolized to amino, and sub-.

stituted hydroxyl capable of being hydrolized to hydroxyl, attached to the carbon atom adjacent the ring, with an agent capable of splitting off the said monovalent substituent. a

2. A process for the manufacture of tetracyclic compounds by ring extension, which comprises reacting a compound of the steroid series which contains at least one hydroaromatic ring having in l'l-position a side chain containing an amino group attached to the carbon atom adjacent thering, with an agent capable of splitting oil the said monovalent substituent, and then treating thecomp'ounds containing new secondary alcohol groups with esterifying agents. 1

3. A process'for'jthe'manufacture of tetracycliccompounds 'byiring extension, v Which comprises I reacting a compound of the steroid series which contains at least one hydroaromatic ring having in 17-position' a side chain containing a substituted amino group capable of being hydrolized to amino, attached to the carbon atom adjacent the ring, with an agent capable of splitting off the said monovalent substituent, and then treating the compounds containing new secondary alcohol groups with esteriiying agents.

cent the ring, with an agent capable of splitting 011 the said monovalentsubstituent, and then treating the "compounds containing new second ary alcohol group with esterifying agents;

6. A process for the manufacture of tetracyclic compounds by ring extension, which comprises reacting a compound of the steroid series which contains at least one hydroaromatic ring which possesses in 'l-positionat the same carbon atom a member of the group consisting of amino, hydroxyl, substituted amino capable of being hydrolized to amino, and substituted hydroxyl capable of being hydrolized to hydroxyl, and a side chain containing agreactive monovalent substituentof the group consisting ofyamino, hydroxyl, substituted amino capable of being hydrolized. to amino, and substituted hydroxyl capable of being hydrolized to hydroxyl' attached to the carbon atom adjacentfthe ring, withan agent capable of splitting off the said monovalent substituent. 7. A process for the manufacture of tetracyclic compounds by ringextension, which comprises reacting a compound or -the steroid series which contains at least one hydroaromatic ring having in l'l-position aside chainfl containing a reactive monovalent substituent, selected from the group consisting of amino, hydroxyl, substituted amino capable of being hydrolized to amino, and substituted hydroxyl capable of being hydrolized to hydroxyLattached to the carbon atom adjacent thelring, with an agent capable of splitting oil the "said monovalent substituent and simultaneously"'efiecting an oxidation, then reacting the roduct'with a reducing agent capable ofrtransforrningjthenew keto group into a secondary alcohol'group. 4 g 8. A process for the manufacture of tetracycliccompounds by .ring extension, which comprises reacting a compound of the steroidseri'es with a -reducingagent'cap'able of transforming 4. A process for the manufacture of tetracyclic I compounds by ring extension, which comprises reacting a compound of the steroid series which contains at least one hydroaromatic ringhaving in 1'7-position a side chain containing an hydroxyl group, attached to the carbon atom adjacent the ring, with an agent capable of splitting off the said monovalent substituent, and then treating the compounds containing new secondary alcohol groups with esterifying agents.

5. A process for the manufacture of tetracyclic compounds by ring extension, which comprises reacting a compound of the steroid series which contains atleast one hydroaromatic ring having in 17-position a side chain containing a b t the new keto group into a secondary alcohol group.

9. A process for the manufacture of tetracyclic compounds by ring extension, which comprises reacting a compound of the steroid series which contains at least one hydroaromatic ring having in 17-position a side chain containing a reactive monovalent substituent, selected from the group consisting of amino, hydroxyl, substituted amino capable of being hydrolized to amino, and substituted hydroxyl capable of being hydrolized to hydroxyl, attached to the carbon atom adjacent the ring, with an agent capable of splitting off the said monovalent substituent, adding oxygen to the compounds containing new double bonds to form ketones, then treating with a reducing agent capable of trans forming the new keto group into a secondary alcohol group, and finally with esterifying agents.

10. The compounds of the class consisting of the saturated D-homo-steroids and the unsaturated D-homo-steroids which contain at least one tions 3, 4 and 5, and which contain only one substituent in the Doing;

11. The compounde'of' the class comistinl: of

unsaturated D-home-sterrfldsv the saturated and,- of the formula containing atleast one double. bond, starting Ln atleast one of the pos1t1ons-3,4aud 5.,

12L'12he compounds of the class consisting atthe. saturated and unsaturatei Rheum-steroids of the formula wner'emxstands tor a grou which by hydrolysis is convertible l'nto hyd'z'oxyl' amt V stands'for' av group containing only one oxygen afiom. obtainable by oxidation of a me'tfiflene' rou the (insaturated; compounds containing at least-one, double bond starting" in at least one of thepesltions 3, 4 and 5.

13". The compounds or the crassconsfstmg of. the saturated and unsaturated D-homd-steroms ofth'e rormura wherein'Y'stands for a.- group which by is conventible Into hydroxyl andfi stands. fans methylene group.

96,86 double bond starting in at least one of the poshgroup containing only oneoxygen'atom obtainable by oxidation of a-methylene group, the un' saturated compounds containing at least one double bond starting-1n at least one of the positions 3, 4 and 5. v

14. The unsaturated D-homo-sterolds of the formula wherein X stands for a group which by hydrolysis is convertible into hydroxyl and V stands for a group containing only one oxygen atom obtainabr'e by oxidation of a methylene group;

15. The unsaturated D-h'omo-sterfods' of the formula whereln X standsM a member 01- the gr'oupeom mg of an esflerified and Qxretherifle hydroxyl' group and '9 stands {or a. group contadning' ouiy oneoxyg'en' acorn obtainable by oxidation of a metfiyiene reen I I 18 The nnsmurated DFhomo-steroids of the form'tfla v HaC' m V scan for a my a only one oxygen mam mammal: of a name: 

